I guess this all depends on what we call 'social' in this sense. If we take such a broad definition that interaction is the basis of defining a 'social animal'

I guess this all depends on what we call 'social' in this sense. If we take such a broad definition that interaction is the basis of defining a 'social animal' there is nothing on the planet that isnt a social thing. Which is why I simplified the definition down to "requiring socialization to thrive" which clearly is not the case for us as a species. No x is an island.